Effect

Generation II

Spikes sets an entry hazard around the enemy team's field. Pokémon who switch into the spike-ridden field take 12.5% of their maximum HP in damage. Flying-type Pokémon are immune to this damage. The move Rapid Spin removes Spikes around the user.

Generation III

Spikes can now be set up to three times, each increasing the damage done to the opponent upon switching in. One layer of Spikes will damage the opponent Pokémon by 12.5% of its maximum HP, two layers will deal 16.67%, and three layers will deal 25%. Any Pokémon with Levitate will prevent the damage.

Forretress spins around and glowing white spikes comes out of its body and hit the opponent, or Forretress fires black spikes at the opponent that surround it. When the opponent gets pricked by them, it hurts them.

Skarmory spins its body rapidly and multiple glowing metallic red spikes come out of its body and fall onto the battlefield. The spikes sink into the ground when they land. When the opponent switches to another Pokémon, small explosions go off under their feet, hurting them.

Forretrees spins its body rapidly, and multiple pyramid-shaped spikes come out of its body and onto the battlefield. The spikes make the opponent's movements restricted, or Forretress shoots out spikes from the horns sticking out of its body and onto the battlefield.